Bug 1468188

Summary: [Docs][KBase] Cluster migration policy description is not detailed enough
Product: Red Hat Enterprise Virtualization Manager Reporter: Roman Hodain <rhodain>
Component: DocumentationAssignee: rhev-docs <rhev-docs>
Status: CLOSED CURRENTRELEASE QA Contact: rhev-docs <rhev-docs>
Severity: medium Docs Contact:
Priority: unspecified    
Version: 4.1.2CC: lbopf, lsurette, michal.skrivanek, rbalakri, rhodain, srevivo, tjelinek, ykaul, ylavi
Target Milestone: ---Flags: lsvaty: testing_plan_complete-
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Last Closed: 2017-08-11 01:43:21 UTC Type: Bug
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oVirt Team: Docs RHEL 7.3 requirements from Atomic Host:
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Description Roman Hodain 2017-07-06 09:00:43 UTC
Description of problem:
The Cluster migration policy is described in 
 Red Hat Virtualization Administration guide
 5.2.2.3. Migration Policy Settings Explained

The following is not clear:

    - if Auto Converge and compression is used for particular Migration policy

    - What are the boundaries for each of the policy? For example description for "Suspend workload if needed" doe snot specify what it the maximum downtime and  how is the downtime calculated. We actually increasing the downtime if the migration does not converge in this way: 150,200,300,400,500,5000ms. We should sate this for each of the policy. We should also state how much are the CPUs slowed down if the Auto Converge is in use and when we will slow down the CPUs.

This is importatnt for the user for deciding which of the policies they should use.

Comment 1 Lucy Bopf 2017-07-11 00:44:23 UTC
Yaniv, can you help us identify the relevant engineering contact who can provide the requested information?

Comment 2 Yaniv Lavi 2017-07-12 11:15:08 UTC
Can you help or assign someone to do help here?

Comment 3 Michal Skrivanek 2017-07-12 13:27:40 UTC
the explanation is intentionally simplified for end users.
Do you need an explanation for your understanding or do you request to provide all the details how the algorithm works to be somewhere in GUI?

Comment 4 Roman Hodain 2017-07-18 13:21:33 UTC
(In reply to Michal Skrivanek from comment #3)
> the explanation is intentionally simplified for end users.
> Do you need an explanation for your understanding or do you request to
> provide all the details how the algorithm works to be somewhere in GUI?

I got a question from a user which of the policies is suitable for their environment. They did not know based on the description.

Comment 6 Michal Skrivanek 2017-07-18 13:32:13 UTC
sounds like a better fit for KCS. 
there's a good deal of information about the policies on ovirt feature page http://www.ovirt.org/develop/release-management/features/virt/migration-enhancements/

Comment 11 Lucy Bopf 2017-08-11 01:44:28 UTC
Extended details about cluster migration policies are now available in the following KBase Solution:

https://access.redhat.com/solutions/3143541